Nonenzymatic Browning in Amorphous Food Models: Effects of Glass Transition and Water
2002
Lievonen, S.M. | Roos, Y.H.
The effect of glass transition on nonenzymatic browning (NEB) rates of amorphous, L-lysine, and D-xylose containing maltodextrin (MD)- or polyvinylpyrrolidone (PVP)-based food models, equilibrated into a(w) of 0.23, 0.33, or 0.44 was studied. Glass transition temperature, T(g), was measured using DSC and NEB rates, followed spectrophotometrically. Use of citrate buffer as a pH regulator was evaluated. The NEB rates were higher in PVP than in MD models. Arrhenius plots showed nonlinearity in the vicinity of the T(g). Increasing a(w) decreased T(g), but did not affect NEB rates around the T(g). The temperature difference (T - T(g)) was not a sufficient measure of material stability.
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